There is a current unsatisfied need for a selectable yield, lethal to less-than lethal, explosive fragmentation warhead and, more particularly, for a grenade having means for selectively assigning a fragmentation lethality output ranging from full lethality level to that of less than a lethal level. For instance there is a critical need for a single device which in the field can be easily changed quickly from a higher yielding fragment size generating device which can attack vehicles, e.g., to a lesser energetic fragment generating device which can attack humans, e.g. This saves deploying in the field various different kinds of grenades for all the different targets. Of even more use still would be a grenade that can be easily set in the field on a sliding scale from full lethality all the way down to low lethality, or to a stunt level lethality and combinations inbetween.